*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body{
    font-family: Arial, Helvetica,sans-serif;
    line-height: 1.6;
}
ul{
    list-style: none;
}
ul li{
    padding: 5px;
    background: #f4f4f4;
    margin: 5px 0;
}

header{
    background: #f4f4f4;
    padding: 1rem;
    text-align: center;
}
.container{
    margin: auto;
    width: 500px;
    overflow: auto;
    padding: 3rem 2rem;
}
#my-form{

    padding: 2rem;
    background: #f4f4f4;
}
#my-form label{
    display: block;
}
#my-form input[type='text']{
    width: 100%;
    width: 8px;
    margin-bottom: 10px;
    border-radius: 5px;
    border: 1px solid #ccc;
}
.btn{
    display: block;
    width: 100%;
    padding: 10px 15px;
    border: 0;
    background: #333;
    color: #fff;
    border-radius: 5px;
    margin: 5px 0;
}
.btn:hover{
    background: #444;
}
.bg-dark{
    background: #333;
    color: #fff;
}

.error{
    background: orangered;
    padding: 5px;
    color: #fff;
}